Folding mechanism planetary gearing including elliptical pair for collect run



Dec. 30. 1969 '0. SMIL TENS 3,486,748

FOLDING MECHANISM PLANETARY GEARING INCLUDING ELLIPTICAL PAIR FORCOLLECT RUN 4 Sheets-Sheet 1 Filed Feb. 23, 1968 INVENTOR VI OSKARSMILTENS Dec. 30. 1969 o. SMILTENS 3,486,748

FOLDING MECHANISM PLANETARY GEARING INCLUDING ELLIPTICAL PAIR FORCOLLECT RUN Filed Feb. 25, 1968 4 Sheets-Sheet 2 illlii INVENTOR 'OS'KARSMI LTE NS o. SMILTENS 3,486,748 G MECHANISM PLANETARY GEARING INCLUDINGELLIPTICAL PAIR FOR COLLECT RUN Dec. 30. 1969 FOLDIN Filed Feb. 23; 19684 Sheets-Sheet :5

FIG. 3

INVENTOR OSKAR SMILTE NS Dec. 30. 1969 o. SMILTENS 3,486,748

' FOLDING MECHANISM PLANETARY GEARING INCLUDING ELLIPTICAL PAIR FORCOLLECT RUN Filed Feb. 23, 1968 4 Sheets-Sheet 4 'F/Gf 4 INVENTOR OSKARSMILTENS United States Patent a 486 14s FOLDING MECHANISM lLANETARYGEARING INCLUDING ELLIPTICAL PAIR FOR COLLECT RUN Oskar Smiltens, Bronx,N.Y., assignor, by mesne assignments, to James Talcott, Inc., New York,N.Y., a corporation of New York Filed Feb. 23, 1968, Ser. No. 707,894Int. Cl. B65h 45/16 US. Cl. 270-77 6 Claims ABSTRACT OF THE DISCLOSUREBACKGROUND OF THE INVENTION This invention relates to folding cylindermechanisms, such as used with rotary printing machines, and moreparticularly, to so-called 3:2 folders.

In a 3:2 folder, the folding cylinder body has a circumference which isone and a half times that of a printing cylinder and it runs attwo-thirds the angular speed of a printing cylinder. Three products arecarried at 120 intervals around the cylinder, the cylinder productholding mechanism being arranged so that a product is relinquished forfolding into the folding off rolls from each position during eachrotation of the cylinder, for a straight run, and during alternaterotations of the cylinder for a collect run.

An obvious solution to the problem of providing suitable folding blademovements is as shown, for example, in Schmidt Patent 1,118,060, andinvolves the use of only two folding blades in a carrier rotating at oneand one-half times the angular speed of the folding cylinder body. Withsuch an arrangement, all that is required for a collect run is tosilence one of the blades.This arrangement, however, possesses a seriousdrawback, in that the accommodation of the folding blade carrier andassociated parts reduces the cylinder body itself to a comparativelyflimsy structure.

Accordingly, 3:2 folder mechanisms have been designed in which there isa folding blade for each product carrying position of the cylinder bodyand the folding blade carrier rotates at the same angular speed as thecylinder body. This permits the use of adequately strong and massivecylinders with adequate product supporting surfaces, but creates aserious problem in providing for acollect run.

As brought out in more detail at appropriate points in the followingspecification, the requirements of the straight run operation are suchas to determine the geometry of the mechanism within quite narrow limitsand the provision for collect run operation must be worked out withinthose limits. This has proved increasingly hard to do, as speeds ofoperation have progressively increased and a point has been reachedwhere the capability of the folding blade mechanism has become adefinite limitation on the speed of the collect run.

Modern proposals are of a complicated character. One workable solutionis shown in Harless Patent 2,981,540. In this construction, each foldingblade has a drive mechanism including a differential gear and anoscillating gear sector with slider crank drive. The parts involved arenumerous and small, being accommodated in an annular space between thesun gear supporting structure and the peripheral ring gear by which thefolding blade carrier is driven, which annular space may have a radialdimension of only about six inches. The moment of inertia of the partsdriven at fluctuating speed is comparatively small, but the drivingelements are also small. While, as stated, this structure is a workableone, it has been found preferable in the interest of simplicity andmassiveness of elements to restore to a single variable speed drivemechanism for the sun gear itself, as shown in Neal Patent 3,055,657. Inthis structure, which involved the use of a bodily oscillateddifferential, together with a cam drive for it, it was found that, inview of the comparatively high moment of inertia of parts driven atfluctuating speed, and the comparatively great accelerations involved,the loads on the cam elements reached practically possible upper limitseven with attention paid to the selection of the most suitable metals,great precision and the use of the best possible finishes.

Accordingly, a construction eleminating massive elements which wereoscillated about axes at some distance from a principal axis was evolved(Bryer Patent No. 3,144,249). In this construction, a stationary sungear was used for straight run and the sun gear was driven by anindexing drive for the collect run. This drive had several advantages,including a blade tip path in folding position which could be conformedto the straight run tip path about as closely as desired, and therotation of fluctuating speed elements about principal axes of inertia,thus minimizing the torque corresponding to the required acceleration ofparts.

A number of constructions of this last type are in commercial use andperforming satisfactorily. It is, however, apparent that the maximumspeeds obtainable with such contructions have just about been reached,and it has been necessary, again to utilize the best materials andfinishes available and to reduce clearances to a minimum. Disadvantagesof the collect run drive include the need for complex cam track shapesin the indexing drive mechanism, the presence of a number of backlashpoints and the presence of power loops feeding back vibration to thepress drive itself. The further development of 3:2 folder collect rundrive mechanisms appear to be at a standstill, as the possibilities hadabout been exhausted.

Since before the time of the Harless patent above mentioned, it seemedrather obvious that no train of epicyclic gearing, involving simplerotary gears could be used. However, this possibility was made thesubject of an exhaustive theoretical investigation which is believed toconfirm the impracticality of any such procedure. The possibility ofutilizing complex cam-gear driving elements, as, for example, speciallydeveloped gear forms in which the pitch circles took the form of highand low circular dwells joined by suitable rise and fall sections andpairs of such elements were locked together by gear tooth or otherelements to provide a drive were investigated.

In the course of this work, the whole problem was approached de novo,resulting in anextremely simple solution eliminating the defects ofprior folding blade drives, above mentioned, and involving stresses of amoderate character, so that it has not only become possible to meetpresent speed requirements, but to do so with an adequate margin ofsafety, even when the effects of wear are taken into consideration sothat it appears that the folding blade drive mechanism is no longer thebottleneck in obtaining increased speed of press runs under collect runconditions, nor does it appear likely to be such a bottle-neck in thepredictable future as speeds are increased.

It is an object of the invention to provide an improved folding blademechanism including means for shaping the blade tip path in anappropriate manner for cooperation with the folding off rolls.

Another object of the invention is to provide an improved collect rundrive mechanism for the folding blades of a 3 :2 folder.

Another object of the invention is to provide a drive mechanismcombining the straight run and collect run driving elements in a simplemanner.

Still another object of the invention is to provide a folding bladedrive mechanism which eliminates objectionable power loops and thefeeding of vibration back into the press drive.

The drive mechanism of the present invention comprises a sun gear,intermediate satellite gear and a driven gear for the folding bladeshaft, suitably related for straight run operation, together withelliptical gear elements, which may be incorporated integrally with gearmembers including also the satellite and driven gear for a straight run,together with means for shifting from the one drive to the other inchanging from straight run to collect run drive.

A mechanism embodying the invention in a preferred form will now bedescribed with reference to the accompanying drawings, and the featuresforming the invention will then be more particularly pointed out in theappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a vertical axial section of a folding cylinder mechanismembodying the invention in a preferred form;

FIG. 2 is an end elevation view;

FIG. 3 is a section on the line 33 of FIG. 1;

FIG. 4 is a section on the line 4-4 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THIS INVENTION The elementsinvolved in the straight run drive may be, and are shown as,substantially identical to these involved in the above mentioned Bryerpatent (apart from some changes in gear ratios which do not affect thestraight run operation to any appreciable degree, but which are criticalfor the collect run operation, when integrated with the straight runoperation as hereafter described).

The frame structure 1 is bored and countersunk to hold a bushing element2, which is secured in place in the frame as by bolts 3. Element 2 has aconcentric inner bore 4 supporting the bearing 5 for the shaft 6 of thecylinder body 7, the cylinder body rotating about the axis indicated atA The bushing 2 has an eccentric outer surface 8 which supports thebearings 9 for the folding blade carrier disc or spider 10, so that thiselement rotates about an axis indicated at A The eccentricity 0r spacingbetween axes A and A provides for the necessary protrusion of thefolding blades beyond the profile of the cylinder body when tuckingproducts into the bight of the folding off rolls, while keeping theblade tips within the cylinder body profile at other times.

The folding blade carrier disc or spider 10 is equipped with aperipheral gear ring 11, meshing with a drive pinion 12 carried on theoffset shaft 13 (as will be understood, the folding blade carrier disc10 at the opposite end of the machine (not shown) is similarly drivenand shaft 13 is driven off the folding cylinder body, also at theopposite end of the machine, in the usual way).

The drive shaft 14 is connected to the printing machine drive, andthrough bevel gears 15, 16, drives the cylinder body shaft 6. As usual,the folding blade carrier is driven about its eccentric axis A at thesame angular speed as the folding cylinder body 7. The folding bladeshaft element is journaled in the disc 10 by means of bearings 21 andalso supported at its outer end in a bearing 21 mounted in the housingstructure 22, 111 the construction shown, the shaft element 20 issecured to and supports the folding blade element 23 by means of aflanged connection 24. In the lowermost position of a blade, as shown inthe figures, blades 25 protrude beyond the profile of the blade carrierdsic and into the bight of the folding ofi? rolls 26 for tuckingproducts therein. Element 20 comprises a circular driven gear element 27which is rotatably fixed to the blade by the member 20 and is operableduring the straight run and also carries an elliptical driven gearelement 28 which is rotatably fixed to the folding blade through theshaft element 20 and is operable during the collect run.

An intermediate gear 29 is rotatably supported (FIG. 4) by bearings 30on a shaft element 31, which in turn, is secured at one end to thecarrier disc 10 and at the other to the casing structure 22. Thebearings 30 are held in place axially by washer plates 32 and thisentire assembly is free to rotate upon the shaft 31 or slide axiallytherealong. Member 29 has a circular gear 33 rigidly secured to it andadapted to mesh with the gear 27, previously referred to, as shown inthe figures, and an elliptical gear element 34, adapted to mesh with theelliptical gear 28, previously referred to, in another position of themember 29. The gear 33 meshes with a sun gear 35 slidably mounted on theeccentric outer surface 8 of the bushing 2. The sun gear has threading36 to each side of its teeth and collar elements 37 and 38 screwed ontoit. These collar elements serve to locate the gear 33 axially and,hence, to hold it in mesh with gear 27, previously referred to. Theentire sun gear 35 together with its collars is held against rotation bya pair of rods 39 screwed into the collar 38 and 40 and accommodated inbores 41 in the frame structure 1. The rods 39 also serve for shiftingthe sun gear axially along the bushing surface 8, for shifting fromstraight run to collect run. As will be apparent, if the rods 39 arepulled outwardly of the frame, should 37 engaging against gear 33 willmove the gear 33 along with the sun gear 35, maintaining it in meshtherewith, and simultaneously moving the entire structure 29, so thatelliptical gear 34 comes into mesh with elliptical gear 28 while thegear pair 33, 27 are brought out of mesh.

These very simple parts just described, when suitably interrelated asbrought out in the following description, are all that are required toprovide for both the straight run and collect run operations of thefollowing blades.

Each of the bars 39 is formed with rack teeth 42 adjacent its outer end,and these teeth mesh with pinions 43 carried on a cross shaft 44 whichis rotatably mounted in brackets 45 secured to the frame 1 and providedwith gear shift lever 46. Swinging this lever into one extreme position(solid lines in FIG. 1) pushes the bars 39 in, providing for thestraight run, while swinging it to its other extreme position (brokenlines of FIG. 1) pulls the bars outwardly and elements 35, 29 with them,so as to provide for the collect run operation.

It is essential that the elements should be properly aligned at the timethat the shift is made and also operation of the gear shift lever 46should be prevented when they are not so aligned, and the mechanismsutilized for this purpose will now be described.

The gear shift lever has, first of all, the usual catch handle 47pivotally mounted to it at 48. The lower end of this handle engages aspring pressed plunger element 49, the other end of which has a groove50 receiving a solenoid actuated pin 51 operated by solenoid 52. Unlessthe solenoid 52 is energized to withdraw pin 51, the spring pressedplunger 49 cannot be withdrawn from a bore 53 in member 44 secured tothe frame, so that it is impossible to operate the gear shift lever 46unless the solenoid is energized.

The folding blade carrier disc 10 carries a cam point 54 adapted toengage the operating roller 55 of a microswitch 56 for energizing thesolenoid 52. Microswitch 56 is carried on a swinging frame pivotallymounted at 57 and is normally held out of position for engagement of itsroller 55 by the cam point 54. When, however, the press is stopped, asolenoid 58 connected to the pivotal member supporting the microswitchat 59, is energized bringing the microswitch down to operating positionagainst the action of the spring 60. Microswitch 61 having its operatingelement engaging an end of plunger 49, prevents starting of the presswhen the handle 47 is in use. Pin and solenoid elements 51 and 52 areprovided (FIG. 1) for the other extreme position of the shift lever 46.

The folder may be coordinated with the control circuits of the printingmachine in a very simple manner, as by connecting solenoid 58 so as tooperate only when the press drive is stopped and utilizing microswitch56 to energize the solenoids 52. Under such conditions, the shift lever56 can be operated only when the press is stopped and the folding bladecarrier is in proper angular position for shifting the gear member 29.Microswitch 61 may similarly be connected so as to prevent starting thepress unless the handle 46 is in one of its two operating positions.

One of the bars 39 has a pair of notches 62 for accommodating annularplate 63 fixed to the housing 22 when the handle 46 is in either of itstwo extreme positions. During the shifting, the bar is in register witha semicircular recess 64 in plate 63, permitting the required axialmovement of rod 39. The other of the rods 39 (to the right in FIG. 3)has a single notch 62' so as to accommodate the member 63 in anyposition. Bar 39 with notches 62 and the plate 63 with cut outs 64 serveas an additional insurance against attempting to change from straight tocollect run with the elements in improper angular positions and alsoagainst the starting up of the equipment with the elements in partlyshifted position.

OPERATION Assuming the bars 39 to be forced inwardly (to the left ofFIG. 1), so that the parts are arranged for a straight run, theintermediate satellite gear 33 rolls on the sun gear 35 and drives thefolding blade gear 27. The straight run conditions require that thedistance from the carrier rotation axis A to the axis of the foldingblade shaft element 20 be twice the distance from the latter axis to thetip of the folding blade 25. This is a necessary condition for a truehypotrochoidal folding blade tip path. A small variation in thisparticular can be tolerated, the effect being to produce a somewhatprolate (blunt-cusped) tip path, or curate (looped) tip path.

The radial location of the axis of the. folding blade shaft 20 is,however, substantially fixed by the straight run requirements. It isalso necessary that the gear tooth ratio between the sun gear 35 andfolding blade gear 27 be accurately 311. Under these conditions, a threecusped hypotrochoidal straight run folding blade tip path will beproduced as in Patent 3,144,249, and other prior patents mentioned.

While, in prior mechanisms, the sun gear and folding blade shaft gearsizes may be varied over a considerable range, so long as the 3:2 toothratio is maintained, and the intermediate gear (being idle) may be ofany convenient size, the collect run arrangements of the presentinvention require that the straight run gear train have teeth in theratios 3:2:1. Still further requirements exist, as a matter ofconvenience, so that for given diametral pitch, the numbers of teeth inthe gears are substantially determined as, in the particular folderselected as illustrative, 69:46:23.

With respect to the collect run, the first requirement is clearly thatthe folding blade shaft should rotate at an average retrograde speed(with reference to carrier which is one-half its speed for the straightrun, or one and one-half retrograde rotations for every rotation of thecarrier. Such rotation at a uniform speed would be useless as the bladetip path in this case is a lobed, rather 6 than a cuspidal one. It istherefore, necessary to accelerate and decelerate the folding bladerotation so that when it is in the folding position, the tip path mayapproximate to the cuspidal form of the straight run path.

The elliptical gear pair 34-28 comprises elliptical gears having thesame number of teeth, so that the folding blade shaft 20 runs at thesame average speed as member 29 and, hence, one and one-half times theaverage speed of the carrier, as required. The eccentricity of the gearellipses is selected so as to provide a proper hypotrochiodal path forthe folding blade tip in folding position. This is achieved,theoretically, by utilizing an elliptical 'gear pair in which theessentricity of the pitch ellipse is one-third, thus providing in oneposition of the elliptical gears (bottom of FIG. 3) a 2:1 drive ratioand in another a 1:2 drive ratio, so that the elliptical gear pair hasan average drive ratio of 1:1.

Considering now the lowermost folding blade shaft as indicated in FIG. 3with the folding blade of folding position, and the elliptical gear pairdriving at a 2:1 ratio, it will be apparent that at this point and foran infinitesimal distance to either side thereof, the blade tip path isidentical with that for the straight run, for the reason that the driveratio between the elliptical gear pair, at this point, is the same asthe straight run gear pair 33-27. As the carrier is rotated away fromthe position of FIG. 3, the drive ratio of the elliptical gear pairdecreases in a sinusoidal manner, with the result that the gear tip pathforms a somewhat more obtuse cusp that is the case for the straight run,being comparable to a blade tip path shown in prior Harless Patent2,981,540. This path is as fully as satisfactory in the folding actionobtained as that of Patent 3,144,249 and involves less shock.

While the invention has been described and illustrated with respect to acertain preferred embodiment which gives satisfactory results, it willbe understood by those skilled in the art after understanding theprinciple of the invention that various other changes and modificationsmay be made without departing from the spirit and scope of theinvention, and it is intended therefore in the appended claims -to coveall such changes and modifications.

What is claimed is:

1.In a 3:2 printing machine folding mechanism, a rotatable folding bladecarrier, folding blade shafts rotatably journaled in the carrier, a sungear, means mount ing the sun gear concentric with the carrier, andplanet gearing mounted on the carrier for driving the folder bladeshafts, the said planet gearing for each folding blade shaft comprisingstraight run gearing including a driven gear rotatably fixed to thefolding blade shaft for driving the same, an intermediate gear rotatablymounted on the carrier and meshing with the said driven gear and withthe sun gear, these gears having tooth numbers in 1:2:3 ratio; the saidplanet gearing also comprising the collect run operation, a non-circulargear pair having a 1:1 average drive ratio and 2:1 maximum drive ratio,means rotatably fixing the gears of the said pair, respectively, to thefolding blade shaft and to the said intermediate gear, with the gearpair rotation timed to the carrier rotation so that driving at the said2:1 maximum ratio occurs at the time of furthest protrusion of thefolding blade in folding position.

2. Mechanism according to claim 1, comprising means slidably mountingthe sun gear for movement between two predetermined positions, and gearshifting means operable by the sun gear when so moved for shiftingbetween straight run and collect run operation.

3. Mechanism according to claim 2, comprising an adjusting member formoving the sun gear between collect run and straight run positions, anannular element fixed to the housing and rotatable therewith, the saidadjusting member being positioned to interfere with the said annularelement, but having notches for accommodating the said element when theadjusting member is in its collect run and straight run positions, theannular element also having a notch for accommodating movement of thesaid adjusting member, whereby gear shifting is permitted only in apredetermined angular position of the planet gearing.

4. In a 3:2 printing machine folding mechanism, a rotatable foldingblade carrier, folding blade shafts rotata bly journaled in the carrier,a sun gear, means mounting the sun gear concentric with the carrier, andplanet gearing mounted on the carrier for driving the folding bladeshafts for a collect run, the said planet gearing comprising anelliptical gear pair, a satellite gear meshing with the sun gear anddriving one gear of the said pair at a constant speed ratio to thecarrier speed of rotation, the other gear of the said pair driving thefolding blade shafts.

5. In a 312' printing machine folding mechanism, a rotatable foldingblade carrier, folding blade shafts rotatably journaled in the carrier,a sun gear, means mounting the sun gear concentric with the carrier, andplanet gearing mounted on the carrier for driving the folding bladeshafts for a collect run, the said planet gearing comprising for eachfolding blade shaft an elliptical gear pair, the eccentricity of thepitch ellipses being substantially /3, one gear of the said pair drivingthe folding blade shaft, and a satellite'gear meshing with the sun gearand driving the other gear of the said pair at a constant speed ratio tothe carrier speed of rotation.

6. In a 3:2 printing machine folding mechanism, a rotatable foldingblade carrier, folding blade shafts rotatably journaled in the carrier,a sun gear, means mounting the sun gear concentric with the carrier andplanet gearing mounted on the carrier for driving the folding bladeshafts for a collect run, the said planet gearing comprising for eachfolding blade shaft an elliptical gear pair, the eccentricity of thepitch ellipses being substantially /3, one gear of the said pair drivingthe folding blade shaft, and a satellite gear meshing with the sun gearand driving the other gear of the said pair at a constant 3:2 speedratio to the carrier speed of rotation.

References Cited UNITED STATES PATENTS 3,055,657 9/1962 Neal et al. 27(77 EUGENE R. CAPOZIO, Primary Examiner PAUL V. WILLIAMS, AssistantExaminer

